History:
In 1898, Pressed Steel Car Co. built the first all-steel hopper car designated the GL. The Pennsylvania Railroad would purchase several thousand of this design. Due to production backlogs at P.S.C.Co. and flaws in the initial design, the Penny came up with its own all-steel, bottom-discharge hopper car in 1904 designated the GLa. Approximately 30,000 GLa's were produced between 1904 and 1920. The Pennsy also built Gla's for numerous coal companies who were anxious for the well-built and reasonably priced cars. Until the 1960s, this design was one of the three most numerous classes of PRR freight cars. Although by this time, these cars began to rapidly disappear from the PRR roster, a few made it into the Penn Central and even Conrail rosters, lasting into the early 1980s.

Railroad/Company:

The Pennsylvania Railroad (reporting mark PRR) was an American Class I railroad, founded in 1846. Commonly referred to as the "Pennsy," the PRR was headquartered in Philadelphia, Pennsylvania.

The PRR was the largest railroad by traffic and revenue in the U.S. for the first half of the twentieth century. Over the years, it acquired, merged with or owned part of at least 800 other rail lines and companies. At the end of 1925, it operated 10,515 miles of rail line; in the 1920s, it carried nearly three times the traffic as other railroads of comparable length, such as the Union Pacific or Atchison, Topeka & Santa Fe railroads. Its only formidable rival was the New York Central (NYC), which carried around three-quarters of PRR's ton-miles.

At one time, the PRR was the largest publicly traded corporation in the world, with a budget larger than that of the U.S. government and a workforce of about 250,000 people. The corporation still holds the record for the longest continuous dividend history: it paid out annual dividends to shareholders for more than 100 years in a row.

In 1968, PRR merged with rival NYC to form the Penn Central Transportation Company, which filed for bankruptcy within two years. The viable parts were transferred in 1976 to Conrail, which was itself broken up in 1999, with 58 percent of the system going to the Norfolk Southern Railway (NS), including nearly all of the former PRR. Amtrak received the electrified segment east of Harrisburg.